β‘οΈ AC microgrid focuses on grid fitting and grid supporting units to increase stability.
π Different control techniques such as voltage control, current control, and power dispatch are used in AC microgrid.
π DC microgrid is introduced, discussing the differences from AC and the principle of DC voltage control.
π The practical challenges of implementing a DC network led to the shift to AC system.
β‘ AC system's advantage lies in the ability to easily convert voltage levels using transformers.
π Newly developed DC to DC converters have made it possible to have multiple DC levels.
β‘οΈ AC and DC microgrids are used for distributed energy resources.
π AC systems have higher efficiency and better control of power flow.
π DC systems offer advantages such as lower operating expenses, safety, and fewer components.
π‘ DC microgrids can be more reliable, occupy less space, and reduce carbon footprint.
π DC grids can eliminate the need for extra AC to DC converters and reduce the number of energy storage systems.
π DC microgrids have fewer components and energy conversion carriers, making them more economical and reliable.
β‘ DC lines have higher power-carrying capability and lower cable losses compared to AC lines.
π DC systems allow for higher current capability and increased power supply to loads.
π DC microgrids offer voltage control instead of frequency control, leading to more effective power flow balancing.
β‘οΈ Droop control is used to balance power input and output in a microgrid.
π The voltage in a DC microgrid can be controlled using a simple droop control.
π Power flow control is a challenge in DC microgrids, but it can be achieved by controlling the DC voltage.
π‘οΈ Protection is a major concern in the implementation of DC microgrids due to the behavior of fault currents.
π AC microgrids require more current carrying capability and have zero-crossing points to clear faults, while DC microgrids have lower impedance and require new fault interruption devices.
π Research and development are needed for fault detection and current interruption methods in DC microgrids due to the lack of a national zero crossing.
π‘ Modeling the dynamics of power electronics converters is crucial for assessing the behavior of both AC and DC microgrids, with DC converters offering faster response and lower inertia.
π Using an average model simplifies converter analysis and allows for understanding the dynamics depending on control strategies in a DC microgrid.
π‘ In the DC to DC converter, there are different states depending on the switch being on or off, and an average model can be used for linear control considering the omission of nonlinearity.
β‘οΈ Stability analysis in a DC microgrid focuses on voltage control, active power flow, and the inclusion of DC passive components and power electronics converters.